Keep your enemies close

Last night this was the advice given to me by my spouse. As I reflected on this I realized the biggest obstacle in doing this i.e keeping enemies close would require me to give up my ego. And this is huge. But the end result would be great because:
I would not be spending time in negative thoughts/action
It would not deter my health
I would master the art of diplomacy
I would not run away from the situation

What do you have to say?